http://www.digginter.com/Shopping/protein-skimmers-and-best-aquarium-protein-skimmer-for-saltwater/ A protein skimmer, or in other words a foam fractionator, is a crucial device mostly used in saltwater aquaria. Its function is to remove organic compounds from the water before they break down into nitrogenous waste. Mon, 25 Jan 2010 14:56:07 CST en